Dry feeding and measuring machine



Oct. 2, 1928. 1,686,077

W. EVANS DRY FEEDING AND MEASURING MACHINE Filed Oct. 7, 1927 2 Sheets-Sheet 1 Oct. 2, 1928.

W. EVANS DRY FEEDING AND MEASURING MACHINE Fiied Oct. 7, 1927 2 Sheets-Sheet 2 f2? ye% for aka/z 17/4276;

Z Y fzzarzzejas Patented Oct. 2, 1928.

UNITED STATES WILSON EVANS, OF CHICAGO, ILLINOIS,

OF DELAWARE.

PATENT; OFFICE).

AssreNon, BY MESNE nssrenminrs, 'ro' NATIONAL ALUMINATE coarommron, or CHICAGO, rumors, A CORPORATION DRY FEEDING AND MEASURING MACHINE.

Application filed .October 7, 1927. Serial No. 224,597.

My invention relates to improvements in dry feeding and measuring machines. This invention is particularly well adapted to feeding such chemicals as sodium aluminate and other similar heavy chemicals having a very great angle of repose.

Sodium aluminate for instance when in the dry form is an exceedingly heavy powder like substance. Its coefficient of friction is so high that if a hopper filled with sodium aluminate having a conical bottom is opened at the apex of the cone, only that part of the mass of sodium aluminate immediately above the opening will fall out and you will then have a hopper filled with sodium aluminate with a cylindrical wall extending clear up from the mass through the discharge opening. If an efiort is made-to dislodge this mass of material a great amount of poweris required owing to the high coefiicient of friction and to the great weight of the material. Many efiorts have been made to solve this roblem, heavy paddles, vibrating machines, ragging chains, telescoping or moving funnels and the like have been tried, all of them perhaps with some measure of success but all of them involving great complication, special machinery and requiring relatively large power.

My invention is primarily 1ntended to be used in connection with or feeding and conveying of sodium aluminate and similar finely divided chemicals where it is exceedingly desirable to take up as little room as possible with the apparatus, to have it as simple as possible and to have it require a minimum amount I of power for operation.

I have illustrated my invention in connect on with a feedingand conveying mechanism adapted for use in connection with water softening plants wherein my device measures out a prearranged quantity of dry chemical 'andsupplies it to a conveying means, whence it is discharged into a water treatment tank. But it will, of course, be quite obvious that my feeder might equally well be adapted to any situation where dry feeding of materials liable to bridge or able to stand by themselves is involved.

ltn carrying out my invention I propose to add to the ordinary type of downwardly increasing'conical bottom, a series of separate inwardly inclined and downwardly decreasthe lower position.

ing funnels or spouts. These funnels or spouts are preferably circular in cross section,

together they substantially fill the space at the a bottom of the hopper leaving little if any area upon whichawall of material may stand at their upper ends and such that they substantially fill the bottom or discharge end of the apparatus.

My invention is illustrated more or less diagrammatically in the accompanying drawings, wherein-- I a Figure 1 is a side elevation of the feeding apparatus;

Flgure 2 is a section along the line 2-2 of Figure 1; y

Figure 3 is a section along the line 3-3 of Figure 1;

C Figure 4 is of funnels; s

Figure 5 is a section along the line 5--5 of Figure 2; a

Figure 6 is a modified form; Figure? is a section along the line 7-7 of Figure 6.

e side elevation of the battery Like parts are indicated by like characters throughout the several figures.

A is a cylindrical feed hopper having a downwardly tapered conical bottom A? which is mounted on the supportiiig le s or framework A. A i'sa cylindricaldisejiarge sleeve extending downwardly from thebottomof the hopper and discharging againstfa rotating plate A". A is an adjusting sleeve slidable on the sleeve A and capable of adjustment up and down by means of the connecting rod A threaded at A carrying'an adjustin'gscrew,

A engaging a bracket A with springA tending normally to force the sleeve A? into B is a motor driving a fan 18 which dis- 1 charges dust laden'air through a conveyer i. pipe B B is a funnelthrough which air tiall the radius of the disc so as to serve as a propeller blade to scrape material off the disc and discharge it into the funnel B It will be noted that material piles up on the disc as indicated atv B when the blade scrapes off material as it comes around to supply the fan with a measured quantity of material. B is a s eed reduction gear driven from the fan an motor shaft and driving at low speed a shaft B which carries the disc A*, so that as .the fan is driven by the motor the measurin disc A is rotated and material is scra d o i it at a fixed rate of speed, the amount 0 material being scraped ofi per revolution depends u on the height of the pile B and the height of the pile is controlled by adjusting the height of the adjusting sleeve A above the plate A.

With material such as sodium aluminate and without an additional means for insuring feeding of the material, a cylindrical column will drop out of the center of the hopper in line with and the same diameter as the column passing down out of the sleeve A. The remainder of the material will remain in the ho per and will not flow. It is to insure'the ow of all the material that my invention is added to the elements above de scribed.

C is a circular plate of the same substanoutside diameter as the inner diameter of t e hopper A. C is a circular plate of slightly lar er diameter than the diameter of the funne A at its lowerqend. Both these plates are apertured, there being a central aperture onthe axial line of each plate anda series of apertures arranged about the central aperture. The sizes of these apertures are such that each of the side apertures are substantially tangent to the central aperture and to the a ertures on either side thereof. It does have 1n each plate a central aperture and in this case six or more apertures grou ed around it, the a ertures in the lower p ate being much smal er than those in the upper plate. Joining the outer apertures are a series of funnels C? C and oining the two central apertures a single funnel C. Preferably the single funnel C is of slightly smaller cross sectional area throughout its len h than the'other funnels, the reason for this ev ing that vertical flow through it is somewhat more rapid than through the inclined fun- .6 surface of the funnels.

nels. By having it somewhat smaller, 'fiow plate surrounding the funnels. This area is so small that the weight of the material itself tends to break down any column structure which might otherwise be formed and the result is that as the rotating disc operates, material flows gradually out of the hop per A through the funnels into the fan and this flow is so regular and level and constant that the discharge through the fan may be accurately measured merely by measuring the difference in length of material in the hopper.

It is obvious that a different arrangement of funnels might under some circumstances be thoroughly efficacious. The'essential feature is that in order to obtain smooth and regular flow of all the material out of a large reservoir through a small discharge opening,

it is necessary to insure that material will be drawn constantly in se arate streams from a suflicent number of su ciently widely spaced points throughout the reservoir to prevent bridging or piling u of the material and it will be understood t at my invention is not limited to the particular mechanism here shown for accomplishing that purpose.

In Figures 6 and 7 the separate dischar e passages are formed in the conical bottom y the provision of a series of radial partitions, which radial partitions form a series of triangular passages, the cross-sectional area of which constantly diminishes downwardly. The. effect is substantiallythe same as the effect of the conical downwardly decreasing discharge passages except that the means for providin them are different and except for the fact t at by this arrangement there are no gravital discharge passa es leading therefrom at widely separate points and converging toward a common discharge point.

2. Feeding means for dry ulverizedmaterial comprising a. receptac e, a series of gravital dlscharge passages leading therefrom, downwardly decreasing in cross sectional area and converging toward a common discharge point.

iaFeeding means for dry ulverized mater' 1 comprising a receptac e, a series of' gravital discharge passages leading therefrom arranged about the central axis thereof, downwardly decreasing in cross sectional area and converging toward a common discharge point. 4. Feeding means-for dry ulverized material comprising a -receptac e, a series of gravity from a receptacle which consists in withdrawing a plurality of separate streams of material from the underside of the receptacle at spaced points thereupon and converging said streams and discharging them at a common discharge point.

6. Feeding means for dry pulverized material comprising a receptacle, a series of gravital. discharge passages leading thererom, each passage eing substantially tangent to those adjacent to it, downwardly decreasing in cross section and converging t0- ward a common discharge point.

7. Feeding means for dry pulverized material comprising a receptacle, a series of gravital discharge passages leading thererom, of circular cross section, each passage being substantially'tangent to those adjacent to it, downwardly decreasing in cross sectional area and converging toward a common discharge point.

8. The combination with a cylindrical receptacle of an apertured bottom plate, a

series of gravital discharge passages, one in register with each aperture in the plate, downwardly decreasing in cross sectional area and converging toward a common discharge point.

9. The combination with a cylindrical re ceptacle having a conical bottom of discharge means therein comprising 'an apertured plate located adjacent the largest portion of the conical bottom, a relatively small apertured plate located adjacent the discharge mouth of the conical bottom, a plurality of gravital discharge passages joining pairs of apertures in said plates and all discharging into the open mouth of the conical bottom.

10. The process of discharging material by gravity from a receptacle which consists in withdrawing a plurality of separate streams of material from the underside of the receptacle at spaced points thereupon and converging said streams and discharging them at a common discharge point, the cross-sectional area of each stream decreasing from the upper toward the lower end thereof.

Signed at Chicago, county of Cook and State of Illinois, this 5th day of October.

WILSON EVANS. 

